Resilient jacket



March 4, 1941. D. A. COLLINGS RESILIENT JACKET Filed July 31, 1939 ENE INVENTOR. DAVID A. COLLINGS ATTORNEY.

Patented Mar. 4, 1941 UNITED STATES PATENT OFFICE RESILIENT JACKET David A. Collings, Cleveland, Ohio, assignorl by mesne assignments, to Hazel K. Hines, Lake- This invention relates to a mold jacket and wood, Ohio Application July 31, 1939, Serial No. 287,589

4 Claims.

method of making same and'is particularly directed to a jacket having corners entirely open but connected with a firm and definite angular and dimensional relation at the corner, capable of yielding under stresses which would damage a rigid jacket but automatically returning to position. The present jacket departs from the two previously known practices of either having a jacket entirely rigid or having the sides mutually entirely loose Within certain limits.

The present which would bend or break a rigid jacket are not reached. When such stresses are reached (usually by rough handling) the spring connections allow the sides to move relatively to one another.

In other words, although the jacket is initially made to rigid accuracy, the corner connections are springs stiff enough to maintain the basic size andangular relations of the jacket walls (usually at right angles and with a few degrees of inward taper from bottom to top), but allow relative movement of the sides before the material of the jacket is bent or broken.

The present application is a continuation in part of my co-pending application Serial No. 226,503, filed August 24, 1938, being a further 30' development of the same principle, and, like that application, is particularly adapted for making flasks out of non-metallic material, such as synthetic fireproof board, of which that commercially known as Transite is an example,

A preferred embodiment of the invention is illustrated in the accompanying drawing and covered by the following description, by way of example.

The preferred embodiment of the invention is illustrated in the drawing herewith, wherein Fig. 1 is a perspective view of my improved jacket Fig. 2 is a plan view of a corner of the same; Fig, 3 is a side and end elevation of a modified corner on a larger scale;

Fig. 4 is a vertical section through a spring attachment pad, on the plane 4-4 of Fig. 2;

Fig. 5 is an elevation of a modified corner connector;

Fig. 6 is a horizontal section substantially on the plane 5-5 of Fig. 4;

same; and

Fig. 8 is a perspective of a spring protector.

The description and illustrations of my im proved jacket show my invention as applied to a 4-sided mold jacket, but it Will be understood that the principles are applicable with special jackets.

As shown in Fig. 1, the jacket comprises separate end slabs I, i and side slabs 2, 2 all generally designated by the word sides, spaced at the ends leaving open corners, and connected at such corners by stiff torsion springs 4, the ends of which are cast or otherwise embedded in fastening pads 5 which may conveniently be of approximately triangular outline and to which the slabs I and 2 are bolted or riveted as at l2,

The springs 4 are coiled, with ends extending at right angles to one another, as at l5 and IS, the ends preferably being brought together so as not to occupy an excessive width, and are cast into the pads 5, which are extra thick as at ll to give a permanent and strong hold over the ends l5, iii of the springs.

The pads are permanently positioned on the ends of the springs with their inner faces at the same vertical and horizontal angle which the jacket walls are to occupy. This is most conveniently done by casting the pads upon the spring ends in a permanent mold or casting jig similar to that shown in Figs. 5, 6 and 7 of Serial No, 226,503. Since all the corners are made in the same jig, the inner face I8 of every pad has the same angle (4 vertical and horizontal in the illustrated jacket) and thus when slabs I and 2 are bolted or riveted onto the pads, the pad faces necessarily set and keep vertical angles A and B, Fig. 4 equal and thus at the intended draft and with horizontal angles also correct, as shown in Fig. 2. The pads are of course initially applied to or formed upon the springs with the springs unstressed.

Various spring modifications may be used, for example the double coil with inner ends 16 in one pad and outer ends I5 in the other, as in Fig. 1; or the two coils 4A, 4A with lower ends ISA embedded as at NA in one of the pads 5A and upper ends 16A similarly embedded in the other pad; or the single coil 4B of Fig. 5.

When the jacket is placed on a sand mold of precisely the jacket dimensions and not forced down thereon, it acts as a rigid jacket because the corner springs are stiff enough not to deflect readily. If the mold is of such a character that the outward pressure of the molten metal is expected to be'greater than the force necessary to bend the unstressed springs, for example a thinwalled mold with a large cavity or with much of the cavity above the parting line, the jacket can be forced further down on the mold, spreading the sides and putting additional tension on the springs, thus adding to the compressive effort of the jacket on the mold.

Due to the resilient corner connections the jacket walls will conform to slightly irregular mold conditions such as are often encountered in practice, such as the mold being out of true either in squareness or taper, resulting usually from being made in a flask which is in bad condition due to abuse, or to wear of the pins or f Mold irregularities of such nature are. frequently not noticeable, but are suflicient to slides.

cause the mold to be damaged by application of a rigid flask. Such damage is often not discovered until shown up by an unusual amount of scrap castings found when the days run is checked up. Applying my resilient jacket does not hurt such molds, because they accommodate themselves thereto, and thus imperfect flasks do not cause bad castings.

Inasmuch as the jacket is entirely open at the corners the vexing problems of makingthe jacket corners fit accurately upon the corners of the mold is entirely avoided, but the unsupported span of sand at the corners is not-great enough to allow the poured metal to break out.

Adjustable jackets with loose hinges at the corners have sometimes been used, but the difficulty with these is that their sides are not firmly held to any basic angles or dimensions, and furthermore, when the limits of play allowed by the looseness are reached, binding occurs. This is avoided in my invention because the ends of the slabs are not at any time in contact, nor are there any attachments to the ends which come into contact. The slabs of my jacket are always held apart by the springs 4 so that there can never be any binding of rigid parts, or any concentration of load at a pinching point. Thus danger of breakage is minimized and there can be no binding.

Each side, with its fastening pads forms a rigid element, just as though the pads and the slabs were integral. are of substantial area so that they firmly position the slabs in the assembly at the correct angle, while the stiffness of the springs assures accurate dimensions from end to end and side to side of the jacket. The effect is of four slabs held entirely out of contact but in a definite spacedf relationship both as'to dimensions and angles,

and each united to the next only by a spring connection of sufiicient rigidity to maintain the relations of the sides in ordinary handling.

In order to protect the springs from being filled with molten metal which may be slopped over from the pouring, I may insert therein pins 2i] The interior faces of the pads modifications within the principles of the invention as set forth in the following claims.

I claim:

1. A foundry jacket comprising a plurality of walls arranged to form a polygonal structure 'liaving 'open corners, and spring connections between adjacent wall ends bridging each corner, said connections each comprising a coiled spring having ends formed in substantially vertical planes at the corner angle of the polygon, a pad cast on each of said ends, said pad having an inner face secured to the back of one of said walls normally to fix the horizontal and vertical angular relation of the walls which 'a're connected by the spring connection. i 2. In a foundry jacket comprising a plurality of walls arranged in a polygonal structure having open corners, and substantially vertical coiled spring connections between adjacent 'w'all ends bridging each corner, a pin in'the coil havingan enlarged head over said coiled spring to-protec-t said coil from spilled molten metal.

'3. In a foundry jacket comprising a plurality.

of walls arranged to form-a polygonal structure having open corners, and "spring connections -between adjacent wall ends bridging each corner, said connections comprising a 'coiledspringwith upright axis and arms of said springiprojecting from said spring along said walls-andconnecte'd thereto, a pin in the coil of'said spring, there being an enlarged head on said pin plac'edover 'said'c'oil to protect said coil'fromspilled molten metal. 7

4. In combination in a foundry jacket comprising four slabs arranged to-forma rectangular structure having open corners, and spring connections between adjacent slab ezidsbiidging each'corner, said connections each comprising' a coiled spring with uprightaxis,arms-projecting from the coil of said spring mutually a't right angles and in planesparallel "each to its respeca tive slab, and a pad cast upon e'achsaid ar'm, each said "pad having 'an inner face secured to the back of its respective slab normally to fixthe horizontal and vertical angular relation of the slabs which are connected by'tliesprin'g con nection; a pin'in the coil *of said springjand a head on said pin covering said "coil 'anfifitting loosely into the open corner betweemthe -"slab' ends, to protect said' coil from spilled molten metal.

n-Avin LAQCOLLINGS. 

